Rob Lowe’s a mad, bad cad!

It’s Rob Lowe as you’ve never seen him! Who knew that a modified Mike Ditka hairdo and the Brawny Paper Towel man’s mustache would do so much for the too-pretty star of “The West Wing” and “St. Elmo’s Fire”?

Let’s face it: Rob Lowe has always been typecast as Ken to every girl’s Barbie. Not anymore. He stars in the title role in “Drew Peterson: Untouchable” (7 p.m., Lifetime) as a creepy, controlling older cop who struts around a small Illinois town like a suburban Casanova. Over the years, he collects four wives. Kathleen (Cara Buono), wife No. 3, dies mysteriously, and Stacy (Kaley Cuoco), wife No. 4, vanishes without a trace.

Based on a true story and filled with real news reports from “Today” and “Larry King Live,” ‘‘Untouchable” opens as Drew is bickering with Kathleen and then cheating on her with Stacy. This is a fun departure for Cuoco, who rapidly transforms from a brazenly clueless, husband-stealing hussy to a doting mom and abused spouse. She is the victimized poster-child-bride for Lifetime’s endless effort to warn women against the wicked wolf disguised as Prince Charming.

The game cast includes Catherine Dent as a concerned neighbor who organizes the effort to put Peterson behind bars. Dent starred on “The Shield,” so she knows a thing or two about abusive, sociopathic policemen.

But the movie belongs to Rob Lowe, whose turn as every woman’s nightmare is a real revelation. From the first scene to the end credits, “Untouchable” remains just this side of camp. But I was transfixed by Lowe’s consistently ominous performance. May his acting career flourish under a continuing assortment of bad hair days.

• John Schneider and Jason London star in the 2011 shocker “Snow Beast” (8 p.m., Syfy). I salute Syfy for treating this movie like the over-the-top joke that it is. On History or Animal Planet, it would be presented as a documentary.